Solution

1. Modify functions.php:

Open the functions.php file in your active theme or create a custom plugin.
Add the following code to enqueue a new stylesheet that will style the "Contribute" tab in the admin area:

function enqueue_contribute_stylesheet() {
    wp_enqueue_style( 'contribute-stylesheet', get_stylesheet_directory_uri() . '/contribute.css' );
}
add_action( 'admin_enqueue_scripts', 'enqueue_contribute_stylesheet' );

2. Create contribute.css:

Create a new file named "contribute.css" in your theme or plugin directory.
Add the required CSS styles to customize the appearance of the "Contribute" tab. For example:

.nav-tab-wrapper .nav-tab[href="admin.php?page=contribute"] {
    /* Add your custom styling here */
}

3. Modify wp-admin/menu.php:

Open the wp-admin/menu.php file in the WordPress core.
Find the section where the menu items are defined.
Add the following code to add the "Contribute" option to the secondary menu:

add_submenu_page(
    'about.php',
    __( 'Contribute', 'text-domain' ),
    __( 'Contribute', 'text-domain' ),
    'read',
    'contribute',
    'contribute_page_callback'
);

4. Create contribute_page_callback():

In the same file or in a separate file included by your theme/plugin, define the callback function for the "contribute" submenu page:

function contribute_page_callback() {
    // Display the content of the "Contribute" page here
    echo '<h1>' . __( 'Contribute', 'text-domain' ) . '</h1>';
    // Add your content and instructions for contributing
}http://